A User Equipment (UE), a method for determining a resource, a method for reporting a resource, and a system for distributing a resource are provided. The method for determining a resource includes: if transmission data on the carrier reaches maximum transmission data supported in a scope allowed by Service Grant (SG), and a transmission power of the UE is capable of improving a data transmission rate of the carrier, and the carrier and the other one carrier of the dual carriers are incapable of completing transmitting total buffer status data in the same delay period, determining that a resource distributed to a UE on one carrier of dual carriers of the UE is insufficient; otherwise, determining that the resource distributed for the UE on the carrier is sufficient. Therefore, a solution for reporting the resource of the dual carriers is provided, so as to improve a network performance.